Radiation Damage Effects in Si Materials and Detectors

Abstract

Silicon sensors, widely used in high energy and nuclear physics experiments, suffer severe radiation damage that leads to degradations in sensor performance. These degradations include significant increases in leakage current, bulk resistivity, space charge concentration, and free carrier trapping. For LHC (Large Hadron Collider) applications, where the total fluence is in the order of 1x1015neq/cm2for 10 years, the increase in space charge concentration has been the main problem since it can significantly increase the sensor full depletion voltage, causing either breakdown if operated at high biases or charge collection loss if operated at lower biases than full depletion. For LHC Upgrade, or the sLHC, however, with an increased total fluence up to 1x1016neq/cm2, the main limiting factor for Si detector operation is the severe trapping of free carriers by radiation-induced defect levels.